Vibratory conveyer



June 29, 948.,

H. H. HETTSQN VIBRATORY CONVEYER Filed May 27 1946 Patented June 29,1948 UNITED STATES PATENT OFFICE VIBRATORY CONVEYER Application May 27,1946, Serial No. 672,402

4 Claims.

This invention relates to a vibratory conveyer including a vibratorymotor or to a. vibratory motor, per se.

An object of the invention ls to provide an lmproved conveyer and motorof the reaction type.

Another object of the invention is to provide improved means includingdiscs, preferably made I of rubber, for guiding a. reaction typearmature and also for providing restoring forces to cooperate withmagnetic or electrical forces to produce vi-bration in an electricalmotor.

Other objects of .the invention will appear hereinafter, the novelfeatures and combinations being set forth in the appended claims.

In the accompanying drawings,

Fig. 1 is a side elevational view of a vibratory feeder or conveyerincorporating the features of my invention;

Fig. `2 is a side view of the motor disconnected from the conveyer deck;

Fig 3 is a longitudinal sectional view taken on the line 3-3 of Fig. 2,looking in the direction of the arrows;

Fig. 4 is a transverse sectional view taken on the line 4-4 of Fig. 2,looking in the direction of the arrows; and

Fig. 5 is a view of a portion of a modified motor.

As illustrated in Fig. 1 of the drawings, the

' vibratory feeder or conveyer includes a deck I0 adapted to be fedmaterial as from a chute II and lto deliver said material to a chute orreceptacle I2. Deck IIJ is mounted on or suspended from asuperstructure, not shown, preferably by four spaced vibration absorbingsuspension mounts I3, there preferably being two on each side thereof.The deck I may be otherwise mounted for unobstructed vibra/tory motion.

Rigidly attached to the deck I Il, as by a. pair of spaced downwardlyextending plates Il, is a vibratory electro-magnetic motor I of thereaction type. The motor I5 includes a field structure I6 which isformed of a pair of laterally spaced longitudinally extending similarcores I'l formed of silicon steel laminations which are preferablyriveted or otherwise atattached together to provide a low reluctancemagnetic path. The field cores I1 are held in proper spaced relation bytop and bottom housing plates IB and I9 which cooperate with the coresI1 to .provide an enclosure for certain elements hereinafter described.

The cores II are provided with spaced poles or projections 20 formingaligned air gaps, such as 2|, between them. A plurality of energizingcoils 22, of which there are three on each side in the structureindicated, are provided and these coils are either connected in seriesor parallel, as desired, or in series parallel combinations to energizethe eld structure I6. Coils 22 may be energized from any desired sourceof alternating or pulsating current by way of conductors 23 which mayinclude an amplitude adjusting rheostat 24 in series therewith. Saidcoils may be energized either from straight alternating current or frompulsating direct current as provided by inserting a rectifier in one ofthe conductors 23 or they may be energized from mixed current in amanner well understood in the art of vibratory conveyors.

An elongated armature 25, madeof stacked silicon laminations, isprovided and said armature 25 is preferably provided with separate polesor projections 26 equal in number to the field poles 20 and spacedcomparably with the spacing of said poles 20.

The adjacent faces of the poles 20 and 2G may be made parallel and theplanes thereof may be Iparallel to the axis of the armature 25 alongwhich it vibrates. However, as illustrated in the drawings, said polefaces are only substantially parallel with said axis and lie in planeswhich make a slight angle to the axis of said armature 25 so that as thearmature 25 moves to the left, as viewed in Fig. 3, of the drawings, theface of each pole 26 will in effect move toward the face of a pole 20along an axis at right angles to the axis of vibration or longitudinalaxis of the armature 25.

The armature 25 includes similar axially extending shafts 21 at oppositeends thereof, which shafts are removably but rigidly attached to centersleeves of resilient discs 28 which are preferably made of rubber. Theperipheries of the discs 28 are preferably rigidly attached to metalliccups 29 which are attached to the upper and lower housing plates I8 andI9 by screws or the like, not shown.

At their outer ends the shafts 2l are provided with adjustable weights30 provided by a plurality of washers, the number and/or size of whichmay be adjusted, said washers 30 being removably held in place between apair of nuts 3| which also co-operate with shoulders on the shafts 21 tomount the armature 25 for unobstructed vibratory motion on the rubberenergy storing discs 28.

As is best illustrated in Figs. 1 and 4 of the drawings, the fieldstructure of the motor I5 is rigidly attached to the deck I0. As aconsequence sad deck I and field structure and all those parts which arerigidly attached to either constitutes one vibratory mass which is arelatively heavy mass as compared with the reaction mass which ishereinafter described, the heavy mass including the deck I0 which is theelement doing work on material to be conveyed, such as granularmaterial.

The armature 25 together with the parts which are rigidly attached toit, including the shafts 21 and adjustable weight discs or washers 30constitutes a reaction mass which has an appreciably less weight thanthat of the field or deck mass. The ratio is preferably at least 4 to 1in favor of the deck or field mass. As a consequence of this fact, inorder for the deck to have sufficient amplitude of vibration, it isevident that the amplitude of vibration of the armature 25 must beconsiderably greater since the relative amplitudes of vibration will beinversely proportional to their weights. That is, the product of theweight of the reaction mass and its amplitude will approximately equalthe product of the field mass and its amplitude for any vibration of themotor I5. To this end the vibratory motor I5 is preferably substantiallyof the indenite stroke type; that expression being used to designate onein which the axis or line of vibration of the armature 25 issubstantially parallel with the planes determining the faces of thepoles 25. In any event there is preferably sufficient clearance in theair gaps 2l so that the armature 25 can vibrate through any desiredangle without the faces of the poles 25 necessarily striking the facesof said poles 20.

Under certain conditions the slight angularity of the faces of saidpoles 25 and 26 may be such as to limit this maximum amplitude ofvibration of the armature 25, but in any event it ls adequate to allow arelatively high amplitude of vibration of said armature 25 and in nocase can said armature 25, when vibrating, move directly toward thefield poles 25.

As clearly illustrated in Fig. 3 of the drawings, the decnergized ornormal position of the armature 25 with respect to the field structureI5 is such that the armature poles 25 are offset laterally or along theaxis of the armature 25 with respect to the poles 2,5. In other words,there is considerable reluctance in each of the air gaps 2|.Consequently whenever current flows in the windings 22 the armature 25will be attracted to the left, as viewed in Fig. 3, or, in other words,so as to tend to reduce the reluctance of the air gaps 2i by attractingthe armature 25. This will happen during each half cycle if the coils 22are energized from alternating current or during each impulse if theyare energized from mixed current or from rectified direct current.

When the armature 25 is thus attracted by magnetic action to move to theleft, as viewed in Fig. 3, the rubber discs perform two importantfunctions. First of all, they operate as frictionless guides to .guidethe armature in rectilinear or straight line motion along the center ofthe motor and thus prevent any sliding frictional contact between anytwo moving parts of the motor. They -are particularly effective toprevent contact between any face of a pole 25 and any face of a pole 20.

Furthermore it is to be noted that the shafts 21 do not slide withrespect to the sleeves of the rubber discs or mountings 25 but arerigidly attached thereto. It may be stated that these rubber discs ormountings 25, 29 are a standard article heretofore commonly employed tomount machinery and to prevent transfer of vibration from a vibratingmachine to a supporting floor, frame or superstructure. 'I'he structureof these mountings, per se, is a well known commercial article.

In addition to the guiding function provided by said mountlngs, thedeflection of the rubber discs 28 also builds up a restoring force sothat as'the alternating flux is reduced or extinguished betweensuccessive impulses vthis restoring force will act to move the armature25 to the right or just the reverse of that to which it is moved by themagnetic attraction. In other words, the current impulses or alternatingcurrent will produce vibration of the armature 25 particularly inco-operation with the restoring force provided by the rubber discs ormounts 25.

The restoring force provided by the discs or mountings 28 is preferablysuch that the motor is tuned to have a natural period of vibration,preferably close Ito though not exactly coincidental with the frequencyor periodicity of the current impulses which energize said motor I5.This natural period of vibration may be adjusted by adjusting theweights 30 for any particular mounts 28. The advantages of this resonanttype operation are well known in vibratory motors and need no Ifurtherelaboration.

In Fig. 5 of the drawings I have shown a modiication of the armature 25,the rest of the motor being the same as that previously described. Inthis structure the armature 25 is provided with energizing coils 32which a-re preferably energized from a source of direct current so as topolarlze said armature 25. If this is done and the field coils 22energized from alternating current the frequency of vibration of thearmature 25 will be cut in half from what it would be if the field coils22 were energized from straight alternating current and thenon-polarized field, as illustrated in Fig. 3, were employed.

The frequency of the source of current may be any commercial frequencyor special frequency, such as 60 cycles, 50 cycles, 30 cycles or 25cycles or, for that matter, even the lower frequencies may .fbespecially generated. It is intended, however, that in most instances themotor will operate from commercially available current whichpredominately are 60 cycles in this country.

It may be pointed out that the motor in both modifica-tions isessentially a magnetic attraction type motor rather than a strictlyelectric motor. That is, the moving .forces derived from the electriccurrent are manifest by magnetic attraction on the iron of the armature25 rather than a structure in which a current carrying coil is impelledbecause of its presence in a magnetic field.

During the operation of the device alternating or pulsatingcurrent willbe supplied to the motor I5. The armature 25 will reciprocaterectilinearly relative to the field structure I5. It will have arelatively large amplitude of vibration because of its relatively smallweight. The energy storing and guiding discs or mounts 25 will guide thearmature 25 for unobstructed frictionless vibration, and the reactionwhich this vibratory mass will have upon the field structure I5 and therigidly attached deck III will be such as to oonvey the usual conveyingand/or vibratory motion to said deck I5.

As clearly illustrated in Fig. 1 of the drawings, the axis of vibrationimparted by the motor I5 to the deck I0 is such as to effect a conveyingaction on any granular material held by said deck l0. Said material willtherefore be conveyed at a rate determined by the amplitude of vibrationof the motor I5, from the left to the right, as viewed in Fig. l of thedrawings.

It is to be particularly noted that this unit has all the desirablecharacteristics of a reaction type motor and that simple, relativelyinexpensive and commercially available energy lstoring rubber springdiscs 28 are provided as the source of mechanical restoring energy toco-operate with magnetic forces to produce the vibration. The cumulativeresult is a very simple, inexpensive and highly efficient reaction typeelectro-magnetic motor.

Obviously those skilled in the art may make various changes in thedetails and arrangement of parts without departing from the spirit andscope of the invention as defined by the claims hereto appended, and Itherefore wish not to be restricted to the precise construction hereindi-sclosed.

Having thus described and shown an embodiment of my invention, what Idesire to secure by Letters Patent o-f the United States is:

1. A vibratory conveyor including a deck adapted to impart vibratorymovement to a load carried thereby, means for imparting vibratorymovement to said deck including a vibratory motor of the reaction type,said motor including a field structure connected to said deck and havingspaced substantially parallel pole faces and having energizing fieldcoil means thereon adapted to be energized from pulsating current, anarmature structure constituting a reaction mass and having appreciablyless weight than said field structure and attached deck, said armatureand field structure having generally parallel pole faces which arenormally slightly offset relative to said field pole faces along theaxis of vibration of said armature whereby when said field coil means isenergized said armature will be magnetically attracted to moverectilinearly substantially parallel with said field pole faces, andmeans mounting said armature for rectilinear vibratory movement relativeto said field structure for unobstructed vibration without slidingfriction, said means including a rubber disc at each end of saidarmature and means attaching the center of each disc to said armatureand its periphery to said field structure, said discs performing thedouble function of guiding said armature for rectilinear movement whilekeeping the armature pole faces out of frictional contact with the eldpole faces and providing restoring force to return said armature to itsnormal position whenever the attracting magnetic forces are reducedsufficiently, all whereby said armature will freely vibrate wheneversaid field structure is energized by undulating current.

2. A vibratory motor including a member adapted to impart vibratorymovement to a load attached thereto, means for imparting vibratorymovement to said member including a vibratory motor of the reactiontype, said motor including a field structure connected to said memberand having spaced substantially parallel pole faces and havingenergizing field coil means thereon adapted to be energized frompulsating current, an armature structure constituting a reaction mas andhaving appreciably less weight than said field structure and attachedmember, said armature and field structure having generally parallel polefaces which are normally slightly offset relative to said field polefaces along the axis of vibration of said armature whereby when saidfield coil means is energized said armature will be magneticallyattracted to move rectilinearly substantially parallel with said fieldpole faces, and means mounting said armature for rectilinear vibratorymovement relativeto said field structure for unobstructed vibrationwithout sliding friction, said means including a rubber disc at each endof said armature and means attaching the center of each disc to saidarmature and its periphery to said field structure, said discsperforming the double function of guiding said armature for rectilinearmovement while keeping the armature pole faces out of frictional contactwith the field pole faces and providing restoring force to return saidarmature to its normal position whenever the attracting magnetic forcesare reduced sufficiently, all whereby said armature will freely vibratewhenever said field structure is energized by undulating current.

3. A vibratory conveyor including a deck adapted to impart vibratorymovement to a load carried thereby, means for imparting vibratorymovement to said deck including a vibratory motor of the reaction type,said motor including a field structure connected to said deck and havingspaced substantially parallel pole faces and having energizing fieldcoil means thereon adapted to be energized from pulsating current, anarmature structure constituting va reaction mass and having appreciablyless weight than said field structure Iand attached deck, said armatureand field structure having generally parallel pole faces which arenormally slightly offset relative to said field pole faces along theaxis of vibration of said armature whereby when said field coil means isenergized said armature will be magnetically attracted to moverectilinearly substantially parallel with said field pole faces, andmeans mounting said armature for rectilinear vibratory movement relativeto said field structure for unobstructed vibration without slidingfriction, said means including a spring member at each end of saidarmature and means attaching the center of each spring member to saidarmature and its periphery to said field structure, said spring membersperforming the double function of guiding said armature for rectilinearmovement while keeping the armature pole faces out of frictional contactwith the field pole faces and providing restoring force to return saidarmature to its normal position whenever the attracting magnetic forcesare reduced sufiiciently, all whereby said armature will freely vibratewhenever said field structure is energized by undulating current.

4. A vibratory motor including a member adapted to impart vibratorymovement to a load attached thereto, means for imparting vibratorymovement to said member including a vibratory motor of the reactiontype, said motor including a field structure connected to said memberand having spaced substantially parallel pole faces and havingenergizing field coil means thereon adapted to be energized frompulsating current, an armature structure constituting a reaction massand having appreciably less weight than said field structure andattached member,l said armature and field structure having generallyparallel pole faces which are normally slightly offset relative to saidfield pole faces along the axis of vibration of said armature wherebywhen said field coil means is energized `said armature will bemagnetically attracted to move rectilinearly substantially parallel withsaid field pole faces, and means mounting said armature for rectilinearvibratory movement relative to said neld structure for unobstructedvibration without sliding friction, said means including a spring memberat each end of said armature and means attaching the center of eachspring member to 5 said armature and its periphery to said neldstructure, said spring members performing the double function of guidingsaid amature for rectilinear movement while keeping the arm'ature polefaces out of frictional contact with the field pole faces and providingrestoring force to return said armature to its normal position whenveverthe attracting magnetic forces are reduced sutllciently, all wherebysaid armature will freely vibrate whenever said field structure isenergized 15 by undulating current.

HARKER H. HITTSON.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED 4STATES E ATENTs

